Anurag Hazra anuraghazra

Realtime Fluid Simulation: Projection

The core of most real-time fluid simulators, like the one in EmberGen, are based on the "Stable Fluids" algorithm by Jos Stam, which to my knowledge was first presented at SIGGRAPH '99. This is a post about one part of this algorithm that's often underestimated: Projection

MG4_F32.mp4

Stable Fluids

The Stable Fluids algorithm solves a subset of the famous "Navier Stokes equations", which describe how fluids interact and move. In particular, it typically solves what's called the "incompressible Euler equations", where viscous forces are often ignored.

In the last years I've been asked multiple times about the comparison between raylib and SDL libraries. Unfortunately, my experience with SDL was quite limited so I couldn't provide a good comparison. In the last two years I've learned about SDL and used it to teach at University so I feel that now I can provide a good comparison between both.

Hope it helps future users to better understand this two libraries internals and functionality.

So you want to write a sync system for a web app with offline and realtime support? Good luck. You might find the following resources useful.

Overview articles

Database in a browser, a spec (Stepan Parunashvili)

What problem are we trying to solve with a sync system?
The web of tomorrow (Nikita Prokopov)

Empty Destructuring Patterns in JavaScript

@RyanCavanaugh posted a fun quiz on Twitter:

Dead Simple package setup for Typescript

Steps

Initial project folder setup:

mkdir mypackage                   # Create a new folder for your package
cd mypackage
pnpm init # Create a brand new package.json

	/**
	* https://github.com/gre/bezier-easing
	* BezierEasing - use bezier curve for transition easing function
	* by Gaëtan Renaudeau 2014 - 2015 – MIT License
	*/

	// These values are established by empiricism with tests (tradeoff: performance VS precision)
	export const NEWTON_ITERATIONS = 4;
	export const NEWTON_MIN_SLOPE = 0.001;
	export const SUBDIVISION_PRECISION = 0.0000001;

	#!/bin/bash

	# exit when any command fails
	set -e

	COMMAND=$1

	function clean() {
	printf "🧹 Cleaning.. \n"
	rm -rf ~/Library/Caches/CocoaPods Pods ~/Library/Developer/Xcode/DerivedData

	/**
	* A logarithmic string length algorithm in the TypeScript type system utilizing
	* a memoizing recursive type. Computes the length of any string with far
	* superior performance than any other current implementations via a doubling
	* cache and string patterns backing the checks. Works for any string with less
	* than 10,000 characters due to the tuple size limits for the cache (in total).
	*
	* @author Carter Snook <[email protected]> github.com/sno2
	* @license https://unlicense.org/ (credit would be nice tho)
	*/

	name: CI
	on:
	push:
	branches:
	- main
	pull_request:
	branches:
	- main
	jobs:
	deploy:

	import { html } from "html-tagged";

	export default function ClientNavigation() {
	return html`
	<script type="module">
	if (typeof navigation !== "undefined") {
	let lastAbortController;
	navigation.addEventListener("navigate", (event) => {
	if (!event.canIntercept) return;